L7 – Logical Data Model
The L7 Logical Data Model View addresses the information perspective on an operational architecture.
Concerns Addressed
- Information Requirements.
- Message Requirements.
- Logical Data Models.
Background
The L7 View is used to document the business information. It describes the information that can be exchanged along the logical flows in the architecture, specified in L3, Node Interactions.
Usage
- Information architecture.
- Information product hierarchy.
Representation
- Entity-Relationship diagram (e.g. IDEF1X).
- UML class diagram.
Detailed View Description
A L7 describes the logical data model for the architecture. It provides a definition of information types (entities), their attributes or characteristics, and their inter- relationships. The entities in the model define the structure of information elements that are exchanged between nodes.
Figure 3-391: Generic Example L7 View
The L7 View defines each kind of information class associated with the architecture domain, mission, or business as its own entity, with its associated attributes and relationships. These entity definitions specify the structure of L3, Node Interactions, information.
Note that NAF refers to ‘information’ in the Logical Specifications layer and ‘data’ in the Physical Specifications layer. The intention of this is that the L7 View describes information of importance to the business (e.g. information products that might be referred to in doctrine, Standard Operating Procedures (SOP) etc.) whereas P7, Physical Data Model, describes how that information is implemented as data structures.
Usually, an entity-relationship notation will be used for L7, but it is also possible to use UML; an example UML usage is shown in Figure 3-402:
Figure 3-402: Example L7 View
Key Elements and Their Relationships
Meta-Model
The detailed meta-model and element list for L7, Logical Data Model, is at paragraph 4.4.7.